The Sciences ACO Light and Matter Museum

Nicolas Arnauda,b,∗, Martine Bessona,b, Henri Borieb, Paul Brunetb, Maurice Chapellierb,c, Andre Damanyb,Elisabeth Dartygeb, Nicolas Deleruea,b, Pierre Dhezb, Yves Ducrosb, Marie-Pauline Gacoinb,d,e,

Jacques Haissinskia,b, Bernard Jean-Mariea,b, Jack Jeanjeanb, Roland Jolivotb, Serge Julliana,b, Guyve Khalilib,f,Jean-Michel Ortegab, Robert Riskallab, Patrick Roudeaua,b, Michel Sommerb, Christophe Sottyb,c,1,

Georges Szklarza,b

aLAL, Univ Paris-Sud, CNRS/IN2P3, Orsay, FrancebThe Sciences ACO association, France

cCSNSM, Univ Paris-Sud, CNRS/IN2P3, Orsay, FrancedFondation de Cooperation Scientifique du campus Paris-Saclay, France

eSynchrotron SOLEIL, L’Orme des Merisiers - Saint-Aubin - BP 48 - 91192 Gif sur Yvette Cedex, FrancefLaboratoire Aime Cotton, CNRS/Univ. Paris-Sud/ENS-Cachan

Abstract

Sciences ACO is a non-profit association based in Orsay (France). It manages a Museum of Light and Mattervisited by more than 1,000 people each year. In this unique place, scientists and cultural mediators preserve, exhibitand comment on items of the history of science & technology, to pass on the knowledge of this heritage to theaudience. Sciences ACO visitors – among them many high school students and teachers – come to learn about theprogress of science and the technology evolution over more than four decades. Sciences ACO is more than just ahistorical museum: it is a driving force for the development for outreach and pedagogical activities on the Paris-SudUniversity campus and in the neighboring towns. The history, the present activity and the prospects of the SciencesACO association are presented in this article.

Keywords:Accelerator, Collider, Education, Museum, Outreach, Storage Ring, Synchrotron light

1. Origin and history of the Sciences ACO associa-tion

1.1. The LAL-LURE accelerator complex

The Sciences ACO museum [1] is located at the cen-tre of the LAL-LURE accelerator complex [2], whichwas awarded the Historic Site label by the EuropeanPhysical Society in September 2013 [3]. This site datesback to 1956 when the ”Laboratoire de l’AccelerateurLineaire” (LAL, today a joint unit of the CNRS/IN2P3

∗Corresponding authorEmail address: narnaud@lal.in2p3.fr (Nicolas Arnaud)

1Now at KU Leuven in the Nuclear Spectroscopy Group.

and of the Paris-Sud University) [4] was set up in Or-say to build and operate a state-of-the-art linear accel-erator (linac). It was operated from 1959 to 2003, pro-viding high intensity electron and positron beams of en-ergy up to 2.3 GeV. In the meantime, many upgradeswere performed to improve its performance and majorfacilities added, ranging from electron-positron collid-ers to synchrotron light sources. In the early 1970’s the”Laboratoire pour l’Utilisation du Rayonnement Elec-tromagnetique” (LURE) was created in close technicalconnection to LAL to develop a wide research programbased on synchrotron light: materials science, chem-istry or structural biology. Nowadays, the LURE hasbecome SOLEIL [5], the French third generation syn-chrotron source (located nearby) while the LAL is still

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Nuclear and Particle Physics Proceedings 273–275 (2016) 1202–1207

2405-6014/© 2015 Elsevier B.V. All rights reserved.

www.elsevier.com/locate/nppp

http://dx.doi.org/10.1016/j.nuclphysbps.2015.09.189

Figure 1: Access map for the Sciences ACO museum.

a major laboratory whose research activities range fromparticipation in the LHC experiments to contributions tothe Planck satellite observations.

1.2. The ACO collider

The ”Anneau de Collisions d’Orsay” (ACO) storedits first beam in 1965, two years after the observationat LAL of the first ever electron-positron collisions withthe AdA collider [6]. Designed and built in Frascati un-der the leadership of Bruno Touschek, AdA was broughtto Orsay in 1962 to benefit from the linac high particleinjection rates. This pioneering work opened an entirelynew field in accelerator science – in particular, the so-called Touschek effect was discovered and understoodwhile AdA was running at LAL.

ACO, whose operation ended in 1988, was first usedas a 1100 MeV electron-positron collider. It lead to im-portant discoveries in accelerator physics and to manypioneering measurements of vector meson properties.In 1973, ACO became the first storage ring in Europeavailable to synchrotron light users. Ten years later, afree-electron laser was successfully operated at ACO –the second in the world, it was the first one in the visiblebandwidth and the first at a storage ring.

Rather than being decommissioned and disassembledlike almost all accelerators in the world once they areturned off, ACO was carefully preserved by the verypeople who worked on it. In 2001, the machine wasrecognized as a French heritage monument.

Figure 2: Aerial view of the LAL in 1981.

1.3. The Sciences ACO Light and Matter Museum

As early as 1993, the ”Sciences ACO” associationwas created by physicists and engineers who worked onthe storage ring. Recognized as a general interest asso-ciation in France in 2011, it is still very active and is nowbringing three generations of scientists together. The as-sociation program is twofold: to circulate the rich ACOhistory (in particle accelerator, collider and synchrotronlight physics) and, based on it, to shed light on today’sscience.

Sciences ACO operates a ”Light and Matter Mu-seum” – see access map in Fig. 1 – open on requestand during special events: European heritage days, na-

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tional science festival, etc. It welcomed about 1,600 vis-itors in 2013 – roughly 50% students and teachers, and50% general public. Joint visits with the historical Sci-ences ACO partners LAL and SOLEIL are often orga-nized, since seeing real scientific and technological in-struments renews the visitors’ attention and makes out-reach conferences more concrete. In addition, SciencesACO is also hosting and organizing various events, inparticular on the theme of art & science. This not onlywidens the museum audience, but it also helps in gettingmore support from local authorities. This complementsthe Sciences ACO primary mission which is to promotescience and make people discover it.

Sciences ACO is more than just a museum display-ing unique items. Thanks to the technical skills of itsmembers and to the countless hours they spend on site,various working instruments are also presented to thepublic. The association has its own workshop adjacentto the display halls. Figure 3 shows a picture of thisworkshop during the maintenance of a ”cosmic arch”,a device designed and built at LAL and which allowsthe public to discover the angular distribution of cosmicmuons.

Figure 3: Maintenance of a ”cosmic arch” in the museum workshop.

2. Permanent exhibitions

2.1. The Pierre Marin hall

Pierre Marin (1927-2002) was a figure of the Frenchaccelerator community, the ACO group leader and oneof the founding fathers of the Science ACO association.After he passed away, his name was rightfully given tothe large hall with thick concrete walls which houses theACO collider – see Fig. 4. Visitors can go around themachine to look at its different components (injection,dipole and quadrupole magnets, RF cavity, vacuum sys-tem, interaction region, see Fig. 5) which are still part oftoday’s colliders or storage rings. In some sense, ACOcan be considered as an ”ancestor” of the CERN LHC.

Figure 4: The ACO collider in the Pierre Marin hall ( c© Claude Men-neglier).

In addition to the ACO collider, various devicesare on display in this exhibition room: detector orig-inal pieces belonging to the H1 [7] and NEMO-3 [8]experiments, educational experiments (cloud chamber,Helmholtz coils, cosmic arch, etc.) and a synchrotronbeamline rebuilt using real historical components.

2.2. The control room of the former LAL linear accel-erator

A new room was opened in the museum in Septem-ber 2013 to display the control room of the former LALlinac. The actual exhibition, seen in Fig. 6, is not anexact replica of the original setup of the control roombut uses optimally the available space to give the visi-tors the best experience made possible by this historical,scientific and technological display. This record of theseventies allows the Sciences ACO guides not only toexplain how this machine was operated and what its per-formances were, but also to shed light on the extraordi-nary advances of electronics and computing since then.

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Figure 6: The LAL linac control room, on display at the Sciences ACO museum since September 2013.

Interactionregion

RFcavity

Vacuumsystem

Injection

Figure 5: Schematics of the ACO ring seen from above, with its maincomponents highlighted.

This exhibit was achieved after years of lobbying,first to preserve this room from disassembly and thento have it moved to Sciences ACO. And this projectcould not have been successful without the dedicationof Henri Borie who has been on the front line since thebeginning of this struggle. The association is currentlyworking on producing supporting material for this newroom: a leaflet and various multimedia resources.

2.3. The Electron Ronde

The Electron ronde, designed and built by the Sci-ences ACO association, is probably the world’s smallestinteractive electron ring model. It includes a table-top10 keV electron linac in which electrons are injected

Figure 7: The Electron ronde.

by a Minitel2 gun. The diameter of its ring, shown inFig. 7, is about 50 cm and the electron trajectory is vis-ible thanks to the helium gas which is injected in thevacuum tube. Magnets of variable strengths show howthe electromagnetic fields act on charged particles andhow these properties are used to steer a beam in an ac-celerator.

This unique equipment is requiring careful operationas it is a prototype whose design is still being optimized.Yet, it has been on display during a two-week CNRS ex-hibition near the Eiffel Tower in 2011 and should also beshown in 2015 at the famous ”Palais de la Decouverte”science museum in Paris.

2The ”Minitel” was a French text-only online service to which endusers could connect through telephone lines, using a computer termi-nal of which millions of copies were produced. This service can beseen as a precursor of the World Wide Web.

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3. Education and outreach activities

The Sciences ACO association is involved in manyeducation and outreach activities whose target rangesfrom high-school students to the general public. Onesuch activity which is worth mentioning is a weekly sci-ence club for a dozen of local school kids which ran forthree years in a row: it was an introduction to every-day physics with a different topic for each session, illus-trated by experiments whose results were used to under-stand properties of the underlying phenomena. Anotherexample is a treasure hunt in the ”Valley of accelera-tors”, organized every year during the open day of thenational science festival: participants are given a map ofthe Orsay campus in which open sites hosting a particleaccelerator are highlighted. At each stage they have tosolve an enigma or answer some questions. A Kinect-based computer game was also developed in associationwith the local Engineer School ”Polytech Paris-Sud [9]:the player’s goal is to make two particle beams collide.Finally, more common outreach activities are also of-fered by the association: public lectures, display of ed-ucational experiments, participation in science and so-ciety debates (e.g. about nuclear energy), etc. Locally,Sciences ACO is also one of the main driving forces ofeducation projects on the campus of the future Paris-Saclay Higher Education Complex.

As already mentioned above, Sciences ACO is re-ally focused on documenting its exhibitions. Variousbrochures are available for visitors while additional ma-terial can be downloaded from the website. Moreover,the association managed to draw technology experts’ at-tention to its museum: two virtual visits are currentlybeing developed – see Fig. 8.

• The first one is based on an online virtualworld and is created by a high-school physicsteacher from Strasbourg, Pierre Wild, and his stu-dents [10]. Ultimately, it could allow to simulate aparticle injection into ACO, steered from the con-trol room of the linac.

• The other uses 360-degree high resolution pictureson which links can be superimposed to navigate inthe museum, open explanatory popup texts, watchvideos, etc. This functionality [11] is provided bySylvain Crouzier from the Paris-Sud University.

4. Prospects and challenges

Since its founding more than 20 years ago, the asso-ciation always had to fight against limited resources –both in terms of manpower and money. It benefits from

Figure 8: Example screenshots of the Sciences ACO virtual visits.Top: a visit included in an online virtual world; bottom: a visit basedon high resolution pictures (here a view of the ACO ring from the top,using a ”mini planet” projection mode).

the support of many partners and institutions: the LALand SOLEIL laboratories; the Paris-Sud University; thedepartment (Essonne) and the region (Ile-de-France);the two neighboring cities Bures-sur-Yvette and Orsay;finally the CNRS/IN2P3.

While extending the size of its exhibition and improv-ing the items on display, Sciences ACO is facing severalrecurring problems. First, its premises are falling intodisuse and require extensive (and expensive!) refurbish-ment. Then, the facility is still classified as nuclear in-stallation and hence its access is strictly controlled; inparticular, all visits must be cleared in advance. This is-sue may be fixed in the near future if the museum mainpiece, namely the ACO storage ring (whose decommis-

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sioning was achieved years ago) could be ”administra-tively decoupled” from the linac areas which are stillradioactive (and closed to the public). Finally, SciencesACO is a remote museum, located on a university cam-pus, which needs to be advertised again and again toattract local people.

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Figure 9: Distribution of the age of the active Sciences ACO members.

A key challenge ahead for the association is shown inFig. 9: the age distribution of the association membersis peaking above 70 years old. To strengthen the workdone so far and continue to grow, Sciences ACO hasto recruit new and younger members who will take overfrom the generation who worked on the storage ring andhad the idea to turn this machine into a museum.

5. Conclusions

The Sciences ACO Light and Matter Museum is aspecial place to talk about the history of science andtechnology over more than four decades. Fueled by theenthusiasm and the energy of the members of the asso-ciation, it displays several rare (if not unique) museog-raphy elements, among which the ACO collider and thecontrol room of the former LAL linac. Hundreds of peo-ple, from school students to the general public, visit itsexhibitions every year and can see home-made educa-tional experiments, like the ”Electron Ronde”.

All of this has been obtained by a small group of ded-icated individuals, within the limited financial resourcesof the association and an essential institutional support.In spite of its past and present achievements, SciencesACO will have to find ways of renewing its membershipin order to amplify its educational and cultural impact.

Acknowledgment

Sciences ACO wishes to thank its long term part-ners whose support is essential to the running of theassociation: the LAL and SOLEIL laboratories; theParis-Sud University; the department (Essonne) andthe region (Ile-de-France); the two neighboring citiesBures-sur-Yvette and Orsay; finally, the CNRS/IN2P3.The association would also like to thank the ”Unitedemantelement de l’installation nucleaire de base 106(LURE)” (UDIL) for its help and support to run the Sci-ences ACO museum during the past decade.

References

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2009.[3] N. Arnaud, J. Haıssinski, The LAL-LURE accelerator complex,

a new EPS historic site, Europhysicsnews 44 (6) (2013) 4–5.[4] Laboratoire de l’Accelerateur Lineaire, http://www.lal.

in2p3.fr.[5] SOLEIL Synchrotron, http://www.synchrotron-soleil.

fr/portal/page/portal/Accueil.[6] C. Bernardini, AdA:The first electron-positron col-

lider, Phys.Perspect. 6 (2004) 156–183. doi:10.1007/

s00016-003-0202-y.[7] The H1 experiment at HERA, http://h1.desy.de.[8] The Neutrino Ettore Majorana Observatory, http://nemo.

in2p3.fr.[9] Polytech Paris-Sud, http://www.polytech.u-psud.fr/

fr/index.html.[10] See for instance http://www.dailymotion.com/video/

x1yq339_jeux-serieux-astroparticules-2014_

school.[11] Visites virtuelles de l’Universite Paris-Sud, http:

//www.visites-virtuelles.u-psud.fr/?s=pano42&s=

pano111&h=32&v=0&f=90.

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